Hitachi has announced that it can now store about 2.5 more data than current HDD's. The company has made improvements to the current perpendicular magnetic recording technology used in hard disks which should become commercially available once some remaining problems are solved.

There are three major improvements that make this possible. By improvements of the magnetic head, improevements of the recording medium and thanks to the adoption of new error correcting codes. If you are interested in more technical details then head over the original article on Tech-On.